Adjustable devices for treating arthritis of the knee

ABSTRACT

A system, and method of using the system, for changing the angle of a bone of a subject is provided by the present disclosure. In one embodiment the system includes a non-invasively adjustable implant configured to be placed inside a longitudinal cavity within the bone and comprising an outer housing and an inner shaft telescopically disposed in the outer housing, at least one of the outer housing and inner shaft associated with a first anchor hole and a second anchor hole, the first anchor hole configured to pass a first anchor for coupling the adjustable implant to a first portion of bone and the second anchor hole configured for to pass a second anchor for coupling the adjustable implant to the first portion of bone, the inner shaft configured to couple to a second portion of bone that is separated or separable from the first portion of bone, such that non-invasive elongation of the adjustable implant causes the inner shaft to extend from the outer housing and to move the first portion of bone and the second portion of bone apart angularly; a driving element configured to be remotely operable to telescopically displace the inner shaft in relation to the outer housing; and wherein the first anchor hole is configured to allow the first anchor to pivot in at least a first angular direction and the second anchor hole is configured to allow the second anchor to translate in at least a first translation direction.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to, and the benefit of, U.S.Provisional Patent Application No. 62/242,931 filed on Oct. 16, 2015.

BACKGROUND Field of the Invention

The field of the invention generally relates to medical devices fortreating knee osteoarthritis.

Description of the Related Art

Knee osteoarthritis is a degenerative disease of the knee joint thataffects a large number of patients, particularly over the age of 40. Theprevalence of this disease has increased significantly over the lastseveral decades, attributed partially, but not completely, to the risingage of the population as well as the increase in obesity. The increasemay also be due to the increase in highly active people within thepopulation. Knee osteoarthritis is caused mainly by long term stresseson the joint that degrade the cartilage covering the articulatingsurfaces of the bones in the joint, including both the femur and tibia.Oftentimes, the problem becomes worse after a trauma event, but can alsobe a hereditary process. Symptoms may include pain, stiffness, reducedrange of motion, swelling, deformity, and muscle weakness, among others.Osteoarthritis may implicate one or more of the three compartments ofthe knee: the medial compartment of the tibiofemoral joint, the lateralcompartment of the tibiofemoral joint, and/or the patellofemoral joint.In severe cases, partial or total replacement of the knee may beperformed to replace diseased portions with new weight bearing surfaces,typically made from implant grade plastics or metals. These operationscan involve significant post-operative pain and generally requiresubstantial physical therapy. The recovery period may last weeks ormonths. Several potential complications of this surgery exist, includingdeep venous thrombosis, loss of motion, infection, and bone fracture.After recovery, surgical patients who have received partial or totalknee replacement must significantly reduce their activity, removing highenergy and impact activities, including running and many other sports,completely from their lifestyle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a desirable alignment of a knee joint.

FIG. 2 illustrates a misaligned knee joint.

FIG. 3 illustrates an open wedge technique in a tibia.

FIG. 4 illustrates an open wedge technique with bone graft inserted anda plate attached.

FIG. 5 illustrates a non-invasively adjustable wedge osteotomy device.

FIG. 6 illustrates a cross-sectional view of the non-invasivelyadjustable wedge osteotomy device of FIG. 5 taken along line 6-6.

FIG. 7 illustrates an exploded view of the non-invasively adjustablewedge osteotomy device of FIG. 5.

FIG. 8 illustrates an external adjustment device.

FIG. 9 illustrates an exploded view of the magnetic handpiece of theexternal adjustment device of FIG. 8.

FIGS. 10-12 illustrate various views of another embodiment of anon-invasively adjustable wedge osteotomy device.

FIG. 13 illustrates an end of the non-invasively adjustable wedgeosteotomy device of FIGS. 10-12.

FIG. 14 illustrates a cross-sectional view of the non-invasivelyadjustable wedge osteotomy device of FIG. 13 taken along line 14-14.

FIG. 15 illustrates a front view of a non-invasively adjustable wedgeosteotomy device in place within a tibia.

FIG. 16 illustrates a side view of a non-invasively adjustable wedgeosteotomy device in place within a tibia.

FIG. 17 illustrates a top view of a non-invasively adjustable wedgeosteotomy device in place within a tibia.

FIG. 18 illustrates a non-invasively adjustable wedge osteotomy devicewithin a tibia in a substantially non-adjusted state.

FIG. 19 illustrates a non-invasively adjustable wedge osteotomy devicewithin a tibia in a first adjusted state.

FIG. 20 illustrates a non-invasively adjustable wedge osteotomy devicewithin a tibia in a second adjusted state.

FIG. 21 illustrates a consolidated tibia after removal of anon-invasively adjustable wedge osteotomy device.

FIG. 22 illustrates a bone screw within a slotted transverse hole of anon-invasively adjustable wedge osteotomy device.

FIGS. 23-25 illustrate various views of another embodiment of anon-invasively adjustable wedge osteotomy device.

FIG. 26 illustrates the non-invasively adjustable wedge osteotomy deviceof FIG. 23 within a tibia in a substantially non-adjusted state.

FIGS. 27-29 illustrate the non-invasively adjustable wedge osteotomydevice of FIG. 23 within a tibia in various states of adjustment.

FIG. 30 illustrates a standard correction for the alignment of a kneejoint.

FIG. 31 illustrates a planned overcorrection for the alignment of a kneejoint.

FIG. 32 illustrates a non-invasively adjustable wedge osteotomy devicewithin a tibia in relation to a standard correction axis and a plannedovercorrection axis.

FIGS. 33-34 illustrate a tapered or hourglass shaped anchor hole of anon-invasively adjustable wedge osteotomy device with an anchor invarious positions.

FIGS. 35-37 illustrate a non-invasively adjustable wedge osteotomydevice having an eccentric bearing in various positions.

FIGS. 38-39 illustrate a knee joint with a non-invasively adjustablewedge osteotomy device implanted in a tibia in various states ofdistraction.

FIG. 40 illustrates an internally threaded anchor hole of an embodimentof the non-invasively adjustable wedge osteotomy device of FIG. 38.

FIG. 41 illustrates a front view of a tibia implanted with an embodimentof a non-invasively adjustable wedge osteotomy device.

FIG. 42 illustrates a top view of the tibia of FIG. 41.

FIGS. 43-44 illustrate a front view of a tibia implanted with anotherembodiment of a non-invasively adjustable wedge osteotomy device invarious states of distraction.

FIGS. 45-46 illustrate a front view of a tibia implanted with anotherembodiment of a non-invasively adjustable wedge osteotomy device invarious states of distraction.

FIGS. 47-50 schematically illustrate various embodiments of a drivingelement of a non-invasively adjustable wedge osteotomy device.

FIG. 51 illustrates a side view of one embodiment of the non-invasivelyadjustable wedge osteotomy device.

FIG. 52 illustrates a cross sectional view of the non-invasivelyadjustable wedge osteotomy device of FIG. 51.

FIG. 53 illustrates yet another view of the non-invasively adjustablewedge osteotomy device of FIGS. 51 and 52.

SUMMARY OF THE INVENTION

In a first embodiment, the disclosure provides a system for changing theangle of a bone of a subject, comprising a non-invasively adjustableimplant configured to be placed inside a longitudinal cavity within thebone and comprising an outer housing and an inner shaft telescopicallydisposed in the outer housing, at least one of the outer housing andinner shaft associated with a first anchor hole and a second anchorhole, the first anchor hole configured to pass a first anchor forcoupling the adjustable implant to a first portion of bone and thesecond anchor hole configured for to pass a second anchor for couplingthe adjustable implant to the first portion of bone, the inner shaftconfigured to couple to a second portion of bone that is separated orseparable from the first portion of bone, such that non-invasiveelongation of the adjustable implant causes the inner shaft to extendfrom the outer housing and to move the first portion of bone and thesecond portion of bone apart angularly; a driving element configured tobe remotely operable to telescopically displace the inner shaft inrelation to the outer housing; and wherein the first anchor hole isconfigured to allow the first anchor to pivot in at least a firstangular direction and the second anchor hole is configured to allow thesecond anchor to translate in at least a first translation direction.

In a second embodiment the disclosure provides a system for changing theangle of a bone of a subject, comprising a non-invasively adjustableimplant configured to be placed inside a longitudinal cavity within thebone and comprising an outer housing and an inner shaft telescopicallydisposed in the outer housing, at least one of the outer housing andinner shaft associated with a first anchor hole, the first anchor holeconfigured to pass a first anchor for coupling the adjustable implant toa first portion of bone, the inner shaft configured to couple to asecond portion of bone that is separated or separable from the firstportion of bone, such that non-invasive elongation of the adjustableimplant causes the inner shaft to extend from the outer housing and tomove the first portion of bone and the second portion of bone apartangularly; and a driving element configured to be remotely operable totelescopically displace the inner shaft in relation to the outerhousing; wherein the first anchor comprises a first end portionconfigured to slide within the slot and into cortical bone at a firstside of the first portion of bone, a second end portion configured toslide within the slot and into cortical bone at a second side of thefirst portion of bone, and an intervening portion configured to residewithin the first anchor hole.

In a third embodiment the disclosure provides a system for changing theangle of a bone of a subject, comprising a non-invasively adjustableimplant configured to be placed inside a longitudinal cavity within thebone and comprising an outer housing and an inner shaft telescopicallydisposed in the outer housing, at least one of the outer housing andinner shaft associated with a first anchor hole, the first anchor holeconfigured to pass a first anchor for coupling the adjustable implant toa first portion of bone, wherein the first anchor hole is configured toallow the first anchor to pivot in at least a first angular direction,the inner shaft configured to couple to a second portion of bone that isseparated or separable from the first portion of bone, such thatnon-invasive elongation of the adjustable implant causes the inner shaftto extend from the outer housing and to move the first portion of boneand the second portion of bone apart angularly; a driving elementconfigured to be remotely operable to telescopically displace the innershaft in relation to the outer housing; and wherein the at least one ofthe outer housing and inner shaft additionally includes two engagementportions configured to rotatably engage a curved anchor.

In a fourth embodiment the disclosure provides a system for changing theangle of a bone of a subject, comprising a non-invasively adjustableimplant configured to be placed inside a longitudinal cavity within thebone and comprising an outer housing and an inner shaft telescopicallydisposed in the outer housing, at least one of the outer housing andinner shaft associated with a first anchor hole, the first anchor holeconfigured to pass a first anchor for coupling the adjustable implant toa first portion of bone wherein the first anchor hole is configured toallow the first anchor to pivot in at least a first angular direction,the inner shaft configured to couple to a second portion of bone that isseparated or separable from the first portion of bone; and a drivingelement configured to rotate a screw threadingly coupled to a nut, thenut comprising an extreme portion configured to contact a location onthe first anchor when the first anchor is within the first anchor hole,such that remote actuation of the drive element causes the screw torotate and to longitudinally displace the nut, thus causing the firstanchor to pivot in the first rotational direction.

In a fifth embodiment the disclosure provides a system for changing theangle of a bone of a subject, comprising a non-invasively adjustableimplant configured to be placed inside a longitudinal cavity within thebone and comprising an outer housing and an inner shaft telescopicallydisposed in the outer housing, at least one end of the non-invasivelyadjustable implant associated with a first anchor hole, the first anchorhole configured to pass a first anchor for coupling the adjustableimplant to a first portion of bone, the inner shaft configured to coupleto a second portion of bone that is separated or separable from thefirst portion of bone, such that non-invasive elongation of theadjustable implant causes the inner shaft to extend from the outerhousing and to move the first portion of bone and the second portion ofbone apart angularly; a driving element configured to be remotelyoperable to telescopically displace the inner shaft in relation to theouter housing; wherein the at least one end of the non-invasivelyadjustable implant is rotatably coupled to at least one of the outerhousing or the inner shaft.

DETAILED DESCRIPTION

In view of the ramifications of partial and/or total knee replacementsurgery, it may be advantageous to intervene early in the progression ofa patient's arthritis. In such cases, knee replacement surgery may bedelayed or even precluded. Osteotomy surgeries may be performed on thefemur or tibia to change the angle between the femur and tibia therebyadjusting the stresses on the different portions of the knee joint. Inclosed wedge or closing wedge osteotomy, an angled wedge of bone may beremoved and the remaining surfaces fused together to create a new,improved bone angle. In open wedge osteotomy, a cut may be made in thebone and the edges of the cut opened to create a new angle. Bone graftmaterial may advantageously be used to fill in the new openedwedge-shaped space, and a plate may be attached to the bone with bonescrews to provide additional structural support. However, obtaining adesired or correct angle during either a closed wedge or open wedgeosteotomy, as described above, is almost always suboptimal. Furthermore,even if the resulting angle is approximately to that desired, there maybe a subsequent loss of correction angle. Other potential complicationsthat may be experienced when using these techniques include nonunion andmaterial failure.

FIG. 1 illustrates a correct/healthy alignment of a femur 100, tibia102, and knee joint 104. In such correct alignments, the a hip joint (ata femur head 108), knee joint 104, and ankle joint (at the midline ofdistal tibia 110) are generally disposed along a single line 112, knownas the mechanical axis. A fibula 106 is shown alongside the tibia 102.By contrast to the knee joint 104 of FIG. 1, the knee joint 104 of FIG.2 is shown in an arthritic state, in which the knee's medial compartment114 (medial meaning situated in or disposed toward the middle or center)has been compromised, causing the line 112 to pass medially off thecenter of the knee joint 104.

FIG. 3 illustrates an open wedge osteotomy 118 formed by making a cutalong a cut line 120, and opening a wedge angle α. FIG. 4 illustratesthe final setting of this open wedge by the placement of bone graftmaterial 122 within the open wedge osteotomy 118, and then placement ofa plate 124, which is then secured to the tibia 102 with tibial screws126. The increase in the wedge angle α can also be described as movingaway from varus and/or moving towards valgus.

FIGS. 5-7 illustrate a non-invasively adjustable wedge osteotomy device300 comprising a magnetically adjustable actuator 342, and having afirst end 326 and a second end 328. An inner shaft 332 having a cavity374 is telescopically coupled to or within an outer housing 330 thatcomprises a distraction housing 312 and a gear housing 306. At least oneproximal transverse hole 305 passes through an end cap 302 located atthe first end 326 of the magnetically adjustable actuator 342. The atleast one proximal transverse hole 305 allows passage of a bone screw,or other fixation device, therethrough to fix the adjustable wedgeosteotomy device 300 to the bone in which it is implanted, e.g., thetibia 102. The end cap 302 may be sealably secured to the gear housing306 by a circumferential weld joint 390. In some embodiments, the endcap 302 may be secured to the gear housing 306 by any appropriate methodof fixation, such as friction, glues, epoxies, or any type of welding.In yet other embodiments, the end cap 302 and the gear housing 306 maybe formed monolithically, or in one piece. A second weld joint 392sealably secures the distraction housing 312 to the gear housing 306. Insome embodiments, the distraction housing 312 may be secured to the gearhousing 306 by any appropriate method of fixation, such as friction,glues, epoxies, or any type of welding. In yet other embodiments, thedistraction housing 312 and the gear housing 306 may be formedmonolithically, or in one piece. One or more distal transverse holes 364pass through the inner shaft 332. The one or more distal transverseholes 364 allows passage of a bone screw, or other fixation device,therethrough to fix the adjustable wedge osteotomy device 300 to thebone in which it is implanted, e.g., the tibia 102. For example, the oneor more distal transverse holes 364 and the at least one proximaltransverse hole 305 allow passage of at least one locking screw. Someembodiments use only one distal transverse hole 364 and one proximaltransverse hole 305 in order to better allow rotational play between themagnetically adjustable actuator 342 and the locking screws as themagnetically adjustable actuator 342 is adjusted.

In some embodiments, one or more longitudinal grooves 372 in the outersurface of the inner shaft 332 engage with protrusions 375 of ananti-rotation ring 373 (Shown in FIG. 7) to advantageously minimize orinhibit rotational movement between the inner shaft 332 and thedistraction housing 312. The anti-rotation ring also engages undercuts333 within end of the distraction housing 312 at a flat edge 384 of theanti-rotation ring 373. One or more guide fins 383 in the anti-rotationring 373 can keep the anti-rotation ring 373 rotationally static withincuts 391 in the distraction housing 312.

The contents of the magnetically adjustable actuator 342 mayadvantageously be protected from bodily fluids. In some embodiments, thecontents of the magnetically adjustable actuator 342 are sealed off fromthe body by one or more o-rings 334 that may reside between the innershaft 332 and the distraction housing 312. For example, one or morecircumferential grooves 382 in the outer surface of the inner shaft 332,for dynamically sealing along the inner surface of the distractionhousing 312. The inner shaft 332 may be extended/retracted axially withrespect to the outer housing 330, for example, by a lead screw 348turned by a cylindrical radially poled magnet 368. The cylindricalradially poled magnet 368 is bonded within a first portion of a magnethousing 308 and a second portion of a magnet housing 310 and isrotatably held on one end by pin 336 and a radial bearing 378, whichdirectly engages the counterbore 304 (shown in FIG. 7) of the end cap302. The second magnet housing 310 is connected to or coupled to a firststage 367 of a planetary gear system 370.

In some embodiments, the planetary gear system 370 may have one stage,two stages, three stages, four stages or even five stages. In otherembodiments, more than five stages may be included, if required. Theembodiment of the planetary gear system 370 shown in FIG. 6 has threestages. Regardless of how many stages are included in the device, theymay work generally according to the description provided below. Theplanet gears 387 of the three planetary gear system 370 turn withininner teeth 321 within the gear housing 306 (shown in FIG. 7). The firststage 367 outputs to a second stage 369, and the second stage 369outputs to a third stage 371. The last or third stage 371 is coupled tothe lead screw 348. In some embodiments, the last or third stage 371 iscoupled to the lead screw 348 by a coupling that allows some degree ofaxial play between the third stage 371 and the lead screw 348, such as,for example, by a locking pin 385 that passes through holes 352 in boththe output of the third stage 371 and in the lead screw 348.Alternatively, the third stage 371 may output directly to the lead screw348. The lead screw 348 threadingly engages with a nut 376 that isbonded within the cavity 374 of the inner shaft 332. Each stage of theplanetary gear system 370 incorporates a gear ratio. In someembodiments, the gear ratio may be 2:1, 3:1, 4:1, 5:1, or 6:1. In otherembodiments, the gear ratio may be even higher than 6:1, if necessary.The overall gear ratio produced by the planetary gear system is equal tothe each side of the gear ratio raised to the number of stages. Forexample, a three (3)-stage system having a gear ratio of 4:1, such asthat shown in FIG. 6, has a final ratio of 4*4*4:1*1*1, or 64:1. A 64:1gear ratio means that 64 turns of the cylindrical radially poled magnet368 cause a single turn of the lead screw 348. In the same way, a two(2)-stage system having a gear ratio of 3:1 has a final ratio of3*3:1*1, or 9:1. In some embodiments, the planetary gear system 370includes stages with different gear ratios. For example, a three-stageplanetary gear system 370 could include a first stage having a gearratio of 4:1, a second stage having a gear ratio of 3:1, and a thirdstage having a ratio of 2:1: that system has a final ratio of4*3*2:1*1*1, or 24:1. It may be desirable to include structural featuresin the housing to absorb axial loads on the cylindrical radially-poledmagnet and/or the planetary gear system 370.

In some embodiments, one or more thrust bearings may be used to absorbaxial loads. For example, thrust bearing 380 may be held loosely in theaxial direction between ledges in the gear housing 306. The thrustbearing 380 is held between a ledge 393 in the gear housing 306 and aninsert 395 at the end of the gear housing 306. The thrust bearing 380advantageously protects the cylindrical radially poled magnet 368, theplanetary gear system 370, the magnet housings 308 and 310, and theradial bearing 378 from unacceptably high compressive forces.

In some embodiments, a lead screw coupler 339 may be held to the leadscrew 348 by the pin 385 passing through hole 359. The lead screwcoupler 339 may include a ledge 355, which is similar to an opposingledge (not shown) at the base of the lead screw 348. In theseembodiments, when the inner shaft 332 is retracted to the minimumlength, the ledge at the base of the lead screw 348 abuts the ledge 355of the lead screw coupler, advantageously preventing the lead screw 348from being jammed against the nut with too high of a torque.

A maintenance member 346, or magnetic brake, comprising a magneticmaterial, may be included (e.g., bonded) within the gear housing 306adjacent to the cylindrical radially poled magnet 368. In suchembodiments, the maintenance member 346 can attract a pole of thecylindrical radially poled magnet 368 to minimize unintentional rotationof the cylindrical radially poled magnet 368 (e.g., turning when notbeing adjusted by the external adjustment device 1180, such as duringnormal patient movement or activities). The maintenance member 346 mayadvantageously exert a lesser magnetic force on the cylindrical radiallypoled magnet 368 than the external adjustment device 1180. As such, themaintenance member holds the cylindrical radially poled magnet 368substantially rotationally fixed most of the time (e.g., when not beingadjusted during distraction/retraction). But, when the externaladjustment device 1180 is used, the stronger forces of the externaladjustment device 1180 overcome the force generated by the maintenancemember 346 and turn the cylindrical radially poled magnet 368. In someembodiments, the maintenance member 346 is ‘400 series’ stainless steel.In other embodiments, the maintenance member 346 can be any otherappropriate magnetically permeable material.

The non-invasively adjustable wedge osteotomy device 300 has thecapability to increase or decrease its length by extending the innershaft 332 out from the distraction housing 312 and retracting the innershaft 332 into the distraction housing 312, respectively. Thenon-invasively adjustable wedge osteotomy device 300 has a length oftravel defined as the difference between its length when fully extendedand its length when fully retracted. In some embodiments, the adjustablewedge osteotomy device 300 has a length of travel of less than about 30mm, less than about 24 mm, less than about 18 mm, less than about 12 mm,and less than about 6 mm. In other embodiments, the non-invasivelyadjustable wedge osteotomy device 300 has a length of travel greaterthan 30 mm, or any other length of travel that is clinically meaningful.Interaction between the non-invasively adjustable wedge osteotomy device300 and the magnetic handpiece 1178 of the external adjustment device1180 that causes rotation of the cylindrical radially poled magnet 368causes the inner shaft 332 to retract (depending on the direction ofmagnet rotation) into the distraction housing 312 thereby producing acompressive force, or causes the inner shaft 332 to extend (depending onthe direction of magnet rotation) our from the distraction housing. Theforce that can be produced by the non-invasively adjustable wedgeosteotomy device 300 is determined by a number of factors, including:size of cylindrical radially poled magnet 368, size of the maintenancemember 346, magnetic force produced by the external adjustment device1180 (determined by the size of the magnet(s) of the magnetic handpiece1178), the distance between the magnetic handpiece 1178 and thecylindrical radially poled magnet 368, the number of gear stages, thegear ratio of each gear stage, internal frictional losses within thenon-invasively adjustable wedge osteotomy device 300, etc. In someembodiments, the non-invasively adjustable wedge osteotomy device 300 ina clinical setting (i.e., implanted into an average patient) is capableof generating up to about 300 lbs., up to about 240 lbs., up to about180 lbs., and up to about 120 lbs., or any other force that isclinically meaningful or necessary. In some embodiments, the magnetichandpiece 1178 of the external adjustment device 1180, placed so thatits magnets 1186 are about one-half inch from the cylindrical radiallypoled magnet 368, can achieve a distraction force of about 240 pounds.

Many components of the non-invasively adjustable wedge osteotomy devicemay be made from Titanium, Titanium alloys (e.g., Titanium-6Al-4V),Cobalt Chromium, Stainless Steel, or other alloys. The diameter of thenon-invasively adjustable wedge osteotomy device 300 is dictated by thesize of the medullary canal 130 in the patient's tibia 102. While themedullary canal 130 may be enlarged through reaming or any otherappropriate technique, it is generally desirable to select anon-invasively adjustable wedge osteotomy device 300 having a diameterapproximately the same as or slightly smaller than the diameter ofmedullary canal 130. In some embodiments the non-invasively adjustablewedge osteotomy device 300 has a diameter of less than about 16 mm, lessthan about 14 mm, less than about 12 mm, less than about 10 mm, lessthan about 8 mm, or less than about 6 mm. In some embodiments, any otherdiameter that is clinically meaningful to a given patient may be used.

The non-invasively adjustable wedge osteotomy device 300 may be insertedby hand or may be attached to an insertion tool (for example a drillguide). In some embodiments, an interface 366 comprising an internalthread 397 is located in the end cap 302 for reversible engagement withmale threads of an insertion tool. Alternatively, such engagementfeatures may be located on the end 360 of the inner shaft 332. In otherembodiments, a tether (e.g., a detachable tether) may be attached toeither end of the non-invasively adjustable wedge osteotomy device 300,so that it may be easily removed if placed incorrectly.

FIG. 8 illustrates an embodiment of an external adjustment device 1180that is used to non-invasively adjust the devices and systems describedherein. As shown in FIG. 8, the external adjustment device 1180 mayinclude a magnetic handpiece 1178, a control box 1176, and a powersupply 1174. The control box 1176 may include a control panel 1182having one or more controls (buttons, switches, or tactile feedbackmechanisms (i.e., any feedback mechanism that can be sensed using thesense of touch, including, for example, heat, vibration, change intexture, etc.), motion, audio or light sensors) and a display 1184. Thedisplay 1184 may be visual, auditory, tactile, the like or somecombination of the aforementioned features. The external adjustmentdevice 1180 may contain software that allows input by/from thephysician.

FIG. 9 shows a detail of an embodiment of the magnetic handpiece 1178 ofthe external adjustment device 1180. The magnetic handpiece 1178 mayinclude a plurality of magnets 1186, including 6 magnets, 5 magnets, 4magnets, 3 magnets, or 2 magnets. In some embodiments, the magnetichandpiece 1178 may have only a single magnet. The magnets 1186 may haveany of a number of shapes, including, for example, ovoid, cylindrical,etc. FIG. 9 illustrates a magnetic handpiece 1178 that includes two (2)cylindrical magnets 1186. The magnets 1186 can be rare earth magnets(such as Neodymium-Iron-Boron), and can in some embodiments be radiallypoled. In some embodiments, the magnets 1186 have 2 poles, 4 poles, or 6poles. In other embodiments, the magnets 1186 have more than 6 poles.The magnets 1186 may be bonded or otherwise secured within magnetic cups1187. The magnetic cups 1187 each includes a shaft 1198 that is attachedto a first magnet gear 1212 and a second magnet gear 1214. Theorientation of the poles of each the two magnets 1186 may be generallyfixed with respect to each other. For example, the poles may berotationally locked to one another using a gearing system, which mayinclude a center gear 1210 that meshes with both first magnet gear 1212and second magnet gear 1214. In some embodiments, the north pole of oneof the magnets 1186 turns synchronously with the south pole of the othermagnet 1186, at matching clock positions throughout a complete rotation.That configuration provides an improved torque delivery, for example, toradially poled cylindrical magnet 368. Examples of various externaladjustment devices that may be used to adjust the various non-invasivelyadjustable wedge osteotomy devices disclosed herein are described inU.S. Pat. No. 8,382,756, and U.S. patent application Ser. No.13/172,598, the entirety of which is incorporated by reference herein.

The components of the magnetic handpiece 1178 may be held togetherbetween a magnet plate 1190 and a front plate 1192. Components of themagnetic handpiece 1178 may be protected by a cover 1216. The magnets1186 rotate within a static magnet cover 1188, so that the magnetichandpiece 1178 may be rested directly on the patient without impartingany motion to the external surfaces of the patient (e.g., rubbingagainst or pulling at the skin of the patient). Prior to use, such asactivating a noninvasively adjustable medical device, an operator placesthe magnetic handpiece 1178 on the patient near the implantationlocation of the radially poled cylindrical magnet 368. In someembodiments, a magnet standoff 1194 that is interposed between the twomagnets 1186 contains a viewing window 1196, to aid in placement of themagnetic handpiece 1178 on the patient. For instance, a mark made on thepatient's skin at the appropriate location may be seen through theviewing window 1196 and used to align the magnetic handpiece 1178. Toperform a distraction, an operator may hold the magnetic handpiece 1178by its handles 1200 and depress a distract switch 1228, thereby causingmotor 1202 to drive in a first rotational direction. The motor 1202 mayhave a gear box 1206 which causes the rotational speed of an output gear1204 to be different from the rotational speed of the motor 1202 (forexample, a slower speed or a faster speed). In some embodiments, thegear box 1206 causes the rotational speed of an output gear 1204 to bethe same as the rotational speed of the motor. The output gear 1204 thenturns a reduction gear 1208 which meshes with center gear 1210, causingit to turn at a different rotational speed than the reduction gear 1208.The center gear 1210 meshes with both the first magnet gear 1212 and thesecond magnet gear 1214 turning them at the same rate. Depending on theportion of the body where the magnets 1186 of the magnetic handpiece1178 are located, it may be desirable that the rotation rate of themagnets 1186 be controlled to minimize the induced current densityimparted by magnets 1186 and radially poled cylindrical magnet 368through the tissues and fluids of the body. For example, a magnetrotational speed of 60 revolutions per minute (“RPM”) or less iscontemplated, although other speeds may be used, such as 35 RPM, orless. At any time, the distraction may be lessened by depressing theretract switch 1230, which can be desirable if the patient feelssignificant pain, or numbness in the area in which the noninvasivelyadjustable device has been implanted.

FIGS. 10-12 illustrate a non-invasively adjustable wedge osteotomydevice 400 configured for maximizing the amount of potential increase ofa wedge angle α. As explained with respect to other embodiments (e.g.,the non-invasively adjustable wedge osteotomy device 300), an innershaft 432 is configured to telescopically displace from an outer housing430, such that the length of the non-invasively adjustable wedgeosteotomy device 400 may be increased or decreased. The internalcomponents of the non-invasively adjustable wedge osteotomy device 400may be configured as is described with respect to other embodiments ofthe non-invasively adjustable wedge osteotomy device that are disclosedherein. The inner shaft 432 can include one or more transverse holesthrough which bone anchors or screws can be passed to anchor the device.Such transverse holes may be at any angle with respect to the vertical,and may be at any angle with respect to the horizontal. Desirably, whenthere is more than one transverse hole, the holes should, ideally, notintersect. In some embodiments, the inner shaft 432 includes threetransverse holes 464A, 464B, and 464C for placement of bone screws. Insome embodiments, the transverse hole 464B is generally at a 90° anglein relation to each of transverse holes 464A and 464C, which areapproximately parallel to each other. Like the inner shaft 432, theouter housing 430 can include one or more transverse holes through whichbone anchors or screws can be passed to anchor the device. In someembodiments, the outer housing 430 includes a first transverse hole 405and a second, slotted transverse hole 407. The first transverse hole 405may generally be at a 90° angle in relation to the second, slottedtransverse hole 407. In some embodiments, the first transverse hole 405is configured to extend in a generally lateral to medial direction whenthe non-invasively adjustable wedge osteotomy device 400 is placedwithin the tibia 102 (lateral meaning situated in or disposed toward theside or sides). In some embodiments, the second, slotted transverse hole407 is configured to extend in a generally anterior to posteriordirection when the non-invasively adjustable wedge osteotomy device 400is placed within the tibia 102.

The slotted transverse hole 407 generally extends through two walls 441,443 of the non-invasively adjustable wedge osteotomy device 400 andthrough a center cavity 445 (shown in FIGS. 13-14). The slottedtransverse hole 407 may have a generally oblong shape, with a length “L”and a width “W”. The width W may be configured to be just slightlylarger than a bone screw that is used to secure the non-invasivelyadjustable wedge osteotomy device 400 to a bone, such that the bonescrew is able to pass through the slotted transverse hole 407. Thelength L may be chosen such that the bone screw is able to pivot orangularly displace within the slotted transverse hole 407 up to adesired maximum angulation within a plane (e.g., a plane substantiallyoriented as the coronal plane). In some embodiments, the ratio of lengthL to width W (L/W) is always greater than one (1), but is less thanabout 3, about 2.5, about 2, about 1.5, or about 1.2. By way of example,when the slotted transverse hole 407 is configured to accept a 5 mm bonescrew, the width W may be about 5.05 mm-5.25 mm, about 5.1 mm-5.2 mm, orabout 5.15 mm, and the length L may be about 6 mm-15 mm, about 7.5mm-12.5 mm, or about 8 mm-10 mm. FIG. 14 also illustrates an interface466 having an internal thread 497, which may be used for releasabledetachment of an insertion tool.

In another embodiment illustrated by FIGS. 51-53 one or more of thetransverse holes 2000 of the non-invasively adjustable wedge osteotomydevice 2002 may have a raised portion 2004 substantially centrallylocated within the transverse holes 2000 upon which a bone anchors orscrews 2006 can be passed to anchor the device. In one embodiment, theraised portion 2004 extends generally perpendicular to a longitudinalaxis of the transverse holes 2000 such that the lower surface of thetransverse hole has a decreasing slope from the raised portion to theexterior in each direction. The raised portion 2002 allows the boneanchors or screws 2006 to pivot providing (as shown by arrows in FIG.53) greater bone anchor or screw 2006 angulation. The raised portion2004 may be rounded or it may come to a discrete point within the one ormore of the transverse holes 2000. In in embodiment, the bone anchors orscrews 2006 may have up to about 40 degrees of movement from a firstposition to a second position and more specifically may have about 20degrees of movement from the first position to the second position. Theraised portion 2002 may provide an added advantage in that it allows thebone anchor or screw 2006 to achieve its full range of angulation whilepivoting about a single point rather than two or more points.

FIGS. 15-17 show the non-invasively adjustable wedge osteotomy device400 implanted within a tibia 102 having a medullary canal 130. A hole132 is drilled along a portion of the length of the medullary canal 130,for example by a series of drills or reamers. An osteotomy 118, whichmay be either a single cut or a series of cuts (e.g., a wedge), is madein the tibia 102 to separate the tibia 102 into a first portion 119 anda second portion 121. In some cases, a drill hole 452 may be made, andthen a blade used to make the cut of the osteotomy 118, up to the pointof the drill hole 452. A hinge 450 is thus created at the uncut portionof the tibia 102. Alternatively, the osteotomy 118 may be made entirelythrough the tibia 102 (such an osteotomy is not shown) and a hinge-likedevice may be secured to the lateral side of the tibia 102, adjacent theosteotomy. The hinge-like device may comprise or be similar to the HingePediatric Plating System™ sold by Pega Medical of Laval, Quebec, Canada.In this alternative method, the incision and osteotomy could be madefrom the lateral side instead of the medial side, leaving the medialside without an incision.

Returning to the configurations of FIGS. 15-17, a non-invasivelyadjustable wedge osteotomy device, such as that shown in FIGS. 10-14, isinserted into the hole 132 and secured to the tibia 102 with bone screws(e.g., two or more bone screws 134, 136, 138, 140, 142). In someembodiments, such as those shown in FIGS. 15-17, the outer housing 430is secured to the first portion 119 of the tibia 102 with a first bonescrew 134 delivered through the first transverse hole 405, and a secondbone screw 136 delivered through the slotted transverse hole 407. Theinner shaft 432 is secured to the second portion 121 of the tibia 102with three bone screws 138, 140, 142 delivered through the threetransverse holes 464A, 464B, 464C, respectively. As described, theslotted transverse hole 407 may be configured to allow the second bonescrew 136 to pivot or rock over an angular range, as will be describedfurther with respect to FIGS. 18-22. As shown in FIGS. 15-17, the firstbone screw 134 may be substantially aligned along an Anterior-Posterioraxis (i.e., front to back), and the second bone screw 136 may besubstantially aligned along the Medial-Lateral axis (i.e., side toside), though in both cases, other degrees of angulation are alsocontemplated. The non-invasively adjustable wedge osteotomy device 400is configured to non-invasively distract the first portion 119 of thetibia 102 away from the second portion 121 of the tibia 102, toangularly open the osteotomy 118. With the orientation of the first bonescrew 134 and second bone screw 136 shown in FIG. 17, the first bonescrew 134 may be free to rotate within the hole 405 (FIG. 16), and thesecond bone screw 136 may pivot within the slotted transverse hole 407(FIGS. 15-16).

FIG. 22 demonstrates the pivotability of a bone screw in place within aslotted transverse hole (e.g., the second bone screw 136 within theslotted transverse hole 407). The bone screw may pivot through a pivotangle β in either direction (+β, −β). FIGS. 18-20 demonstrate thenon-invasively adjustable wedge osteotomy device 400 which is implantedin the tibia 102 being adjusted to increase an angle A of the wedgeosteotomy 118. In FIG. 18, the inner shaft 432 extends from the outerhousing 430 an initial length D₁. The osteotomy 118 is in an initialclosed or mostly closed state, and the first bone screw 136 has beensecured to the first portion 119 of the tibia 102 so that it is angledat, near, or towards a first extreme of pivot in a first angulardirection in relation to the slotted transverse hole 407. Morespecifically, the head 144 of the first bone screw 136 on the medialside of the first portion 119 is at a lower height in comparison to thedistal end 148 on the lateral side of the fist portion 119, leaving thefirst bone screw at an angle −β (see FIG. 22). Though the bone screws inFIGS. 18-20 are shown with short proximal male threads 146, other bonescrews may be used, including, for example, lag screws, or fullythreaded screws. In FIG. 19, a distraction of the non-invasivelyadjustable wedge osteotomy device 400 has been performed, causing theinner shaft 432 to extend from the outer housing 430 so that it extendsa new length D₂, which is greater than the initial length D₁. In someembodiments non-invasive distraction may be accomplished by placing themagnetic handpiece 1178 of the external adjustment device 1180 on theskin or clothing in the area of the upper tibia 102 and operating theexternal adjustment device 1180 to rotate the one or more magnets 1186which in turn cause the radially-poled permanent magnet 368 (FIGS. 6-7)within the non-invasively adjustable wedge osteotomy device 400 to bemagnetically rotated. Extension of the inner shaft 432 out of the outerhousing 430 causes the first portion 119 to be lifted away from thesecond portion 121 thereby opening osteotomy 118 to a wedge angle A₂. Asosteotomy 118 is opened, the first bone screw 136, which is secured tothe first portion 119 of the tibia 102, may be rotated with the firstportion 119 (the rotation being allowed/facilitated by the slottedtransverse hole 407). In FIG. 19, the first bone screw 136 is shown witha substantially horizontal orientation (i.e., β≈0°). In FIG. 20,additional distraction has been performed (e.g., non-invasivedistraction) and the inner shaft 432 has been extended further from theouter housing 430 so that it extends a new, increased length D₃. A new,increased wedge angle A₃ of the osteotomy results from the additionalextension of the inner shaft 432, and the first bone screw 136 haspivoted along with the continued rotation of the first portion 119 ofthe tibia 102 until the first bone screw 136 is angled at, near, ortowards a second extreme of pivot in a second angular direction inrelation to the slotted transverse hole 407. More specifically, the head144 of the first bone screw 136 on the medial side of the first portion119 is at a higher height in comparison to the distal end 148 on thelateral side of the first portion 119, leaving the first bone screw atan angle +β (see FIG. 22).

Non-invasive distraction while a patient is awake, mobile, and orweight-bearing may allow an optimum wedge angle A to be achieved. Insome embodiments, an optimum wedge angle is the wedge angle A at whichthe patient feels no pain. In other embodiments, an optimum wedge angleis the wedge angle A at which the patient feels no contact of tissue atthe knee joint, for example at a medial compartment of the knee joint.In some cases, the wedge angle A may be increased until an anatomicalbenchmark is reached, for example a Fujisawa overcorrection, which isdescribed further below. Distractions may be done at specific timeintervals. For example, the total length of a non-invasively adjustablewedge osteotomy device, as disclosed herein, may be increased about 0.5mm-1.5 mm per day, or about 0.75 mm-1.25, or any other clinicallyadvantageous rate, until the desired wedge angle is reached.Alternatively, the amount by which a non-invasively adjustable wedgeosteotomy device, as disclosed herein, is to be lengthened may becalculated prior to each adjustment procedure (e.g., lengthening,distraction, or adjustment), so that a consistent wedge angle increase(i.e., using trigonometric relationships so that the angle can beincreased by a consistent Δβ) is achieved by each adjustment procedure.In some circumstances, any given day's adjustment may be all at once,within a single procedure. Alternatively, any given day's adjustment maybe broken up into two or more smaller adjustments or procedures per day(equivalent to the daily desired total). Breaking up adjustments intosmaller procedures may advantageously help to minimize pain ordiscomfort caused by stretching of soft tissue in the knee joint 104.For some patients or in some circumstances it may be desirable todetermine the desired rate of device distraction based on a rate ofmedial cortex increase (the open portion of the osteotomy 118 at themedial edge of the tibia 102). For example, it may desirable to distractthe device at a rate sufficient to cause the medial cortex to increaseby about 1 mm per day: depending on the width of the tibia 102, amongother factors, such a 1 mm daily medial cortex increase may require onlybetween about 0.5 mm and 0.65 mm daily device distraction (i.e., dailyincrease at the midline). In some cases, once the ultimate desired wedgeangle is reached, distraction is stopped, and the wedge osteotomy 118 isallowed to consolidate over a period of time (e.g., days, weeks, ormonths). The amount of time required for consolidation may depend on theangle of wedge osteotomy 118 increase, the rate of wedge osteotomyincrease, whether the patient smokes, whether the patient has diabetes,and the patient's activity level, among other biological factors. Duringthe distraction process (e.g., from implantation to substantialhealing), it may be desirable for the patient to place a diminished(i.e., less than normal) amount of force (compression) on the leg beingtreated, for example, through the use of crutches, braces, wheel chairs,walkers, or the like. Additionally, the patient may be instructed toincrease the load placed on the leg during the consolidation phase:compression during consolidation has been positively linked to improvedosteogenesis and faster and better healing of the bone.

In some cases, after the consolidation phase has substantiallycompleted, the devices discloses herein, including the non-invasivelyadjustable wedge osteotomy device 400 and the bone screws 134, 136, 138,140, 142 may be removed. A revised tibia 102, after removal of a thenon-invasively adjustable wedge osteotomy device, as disclosed herein,is shown in FIG. 21. During the distraction phase and/or theconsolidation phase, bone graft may be added to portions of the wedgeosteotomy 118 in order to help increase solidification of the tibia 102,for example, between the first portion 119 and the second portion 121.

FIG. 30 shows the mechanical axis 112 of a tibia 102 that has beenadjusted by creating a wedge osteotomy, for example, by using standardmethods or the apparatuses and/or methods described herein. Themechanical axis extends from the femur head 108, through the center ofthe knee joint 104, and to a center point of the ankle joint at thedistal tibia 110. Although restoring the mechanical axis 112 through thecenter of the knee joint 104 has been standard practice in some centers,an alternative method was proposed by Fujisawa (see Fujisawa et al.,“The Effect of High Tibial Osteotomy on Osteoarthritis of the Knee: AnArthroscopic Study of 54 Knee Joints”, July 1979, Orthopedic Clinics ofNorth America, Volume 10, Number 3, Pages 585-608, the entirety of whichis incorporated by reference herein). Fujisawa states that “the idealcorrection method is to align the mechanical axis to pass through apoint 30 to 40 percent lateral to the midpoint.” (Fujisawa et al. atPages 606-607) An overcorrection axis 150, as taught by Fujisawa, isshown in FIGS. 30-31 and passes through the knee joint 104 at a pointthat is about 30%-40% lateral of the midpoint in the knee joint 104. Asthe standard mechanical axis passes through the midpoint in the kneejoint 104, the overcorrection axis 150 is about the same percentagelateral to the standard mechanical axis 112. FIG. 31 shows anovercorrection performed by wedge osteotomy of the tibia 102 thatreaches approximately the conditions described by Fujisawa. Anovercorrected mechanical axis 152 approximates the overcorrection axis150 through the knee joint 104, extending from the center of the femurhead 108 through the knee joint at approximately the overcorrection axis150, and to the center point of the ankle joint at the distal tibia 110.To achieve overcorrection, the angle of the wedge osteotomy 118 has beenincreased an additional amount.

FIG. 32 illustrates an embodiment of a non-invasively adjustable wedgeosteotomy device, for example the non-invasively adjustable wedgeosteotomy device 400, in place within the tibia 102, with the standardmechanical axis 112 and the overcorrection axis 150 indicated.Overcorrection axis 150 is shown a distance x lateral to the standardmechanical axis. In some embodiments, distance x is between about24%-44%, about 28%-40%, about 30%-38%, and about 32-36% of the totaldistance from the midline to the lateral extreme. In FIG. 32, the angleof midline correction (“A_(MC)”) was performed in order to achieve themechanical axis 112 as shown. The A_(MC) is defined as the amount ofangle of correction required to place the mechanical axis through thecenter of the knee joint 104, may be up to about 12° or less in manypatients, and may be achieved by using non-invasively adjustable wedgeosteotomy devices as disclosed herein. In some cases, an angle ofgreater than 12° is required to achieve a proper overcorrection asdescribed above (e.g., it may be desirable in some patients to achievean angle of up to about 16°, or even more). Thus, an additional angle ofovercorrection (“A_(OC)”), may be needed in order to create theovercorrected mechanical axis 152 as in FIG. 31. In some cases theA_(OC) may be between about 1°-8°, about 2°-7°, about 3°-6°, and about4°-5°, or the A_(OC) may be any other angle that is physiologicallybeneficial for the patient. The total resulting correction angle istherefore equal to the sum of angles A_(MC) and A_(OC).

Another embodiment of a non-invasively adjustable wedge osteotomy device500, illustrated in FIGS. 23-25, may be configured to allow for anincreased amount of angular correction in the tibia 102. Thenon-invasively adjustable wedge osteotomy device 500 includes an innershaft 532, which is telescopically distractable from an outer housing530. In some embodiments, the internal components of the non-invasivelyadjustable wedge osteotomy device 500 may be similar or identical tothose of the other non-invasively adjustable wedge osteotomy devicesdisclosed herein (for example the non-invasively adjustable wedgeosteotomy device 300 of FIGS. 5-6, among others). In some embodiments, aslotted transverse hole 507 extends through the outer housing 530 of thenon-invasively adjustable wedge osteotomy device 500. The slottedtransverse hole 507 has a generally oblong shape, similar to thatdescribed with respect to the embodiments of the non-invasivelyadjustable wedge osteotomy device shown in FIGS. 10-14. Additionally,the outer housing 530 may have a second slotted hole 586. While theslotted transverse hole 507 may be generally vertically oblong, thesecond slotted hole 586 may be generally horizontally oblong. The secondslotted hole 586 may have a length L and a width W, as shown in FIG. 24.The length L may be configured to be slightly larger than the diameterof a bone screw that is used to secure the non-invasively adjustablewedge osteotomy device 500 to a bone, such that the bone screw is ableto pass through the second slotted hole 586. The width W may be chosensuch that the bone screw is able to horizontally pivot or angularlydisplace within the second slotted hole 586. In some embodiments thesecond slotted hole 586 is configured to be used with a 5 mm bone screw,the length L may be about 5 mm to about 5.2 mm, or about 5.1 mm, and thewidth W may be about 6 mm to about 9 mm or about 7 mm. In someembodiments, the ratio of width W to length L (i.e., W/L) may be betweenabout 1.08 and about 1.65, or about 1.25 to about 1.54, or about 1.37.The slotted transverse hole 507 and the second slotted hole 586 arelocated near a first end 568 of the outer housing 530. As shown in FIG.25, a second end 570 of the outer housing 530 is angled from the firstend 568 at a transition point 572. In some embodiments, the angle 578 isbetween about 2°-18°, about 4°-16°, about 6°-14°, about 8°-12°, andabout 10°, or any other angle that is clinically meaningful for anygiven patient. The second slotted hole 586 may include an anterioropening 588 and a posterior opening 590, which may be oriented inrelation to the first end 568 at an angle 576. In some embodiments, theangle 576 is between about 70°-100°, about 75°-95°, about 80°-90°, orabout 85°, or any other angle that is clinically meaningful for anygiven patient. FIG. 23 also illustrates an interface 566 having aninternal thread 597, which may be used for releasable detachment of aninsertion tool. Similar to what has been described above, thenon-invasively adjustable wedge osteotomy device 500 may be inserted byhand or may be attached to an insertion tool (for example a drillguide). In some embodiments, an interface 566 comprising an internalthread 597 is located at or near the first end 568 for reversibleengagement with male threads of an insertion tool. Alternatively, suchengagement features may be located at or near the inner shaft 532. Inother embodiments a tether (e.g., a detachable tether) may be attachedto either end of the non-invasively adjustable wedge osteotomy device500, so that it may be easily removed if placed incorrectly.

FIGS. 26-29 illustrate how the second slotted hole 586 of thenon-invasively adjustable wedge osteotomy device 500 works inconjunction with the slotted transverse hole 507 to advantageouslyfacilitate the possibility of an increased amount of angular correctionbetween a first portion 119 and second portion 121 of the tibia 102.First bone screw 134 is illustrated without a head merely so the shaftof the first bone screw 134 is visible within the second slotted hole586. In FIG. 26, the osteotomy 118 is substantially closed and the innershaft 532 has not been significantly distracted from the outer housing530. The first bone screw 134 may (at least initially) preferably becentrally oriented with respect to the width W of the second slottedhole 586. In FIG. 27, the inner shaft 532 has been distracted furtherout of the outer housing 530. As the outer housing 530 moves, it pushesup on the first bone screw 134 and the second bone screw 136, which inturn push upward on the first portion of the tibia 102, causing thefirst portion of the tibia 119 to pivot about the hinge. As the firstportion of the tibia pivots, the second bone screw 136 pivots within theslotted transverse hole 507, as described with respect to otherembodiments disclosed herein, such as the non-invasively adjustablewedge osteotomy device 400. While the second bone screw 136 pivots, thefirst bone screw 134 may slide medially (i.e., towards the left side ofFIG. 27). In FIG. 28, the inner shaft 532 has been distracted stillfurther out of the outer housing 530. As the second bone screw 136pivots even further within the slotted transverse hole 507, the firstbone screw 134 may be forced back towards a central location withrespect to the width W of the second slotted hole 586. In FIG. 29, theinner shaft 532 is distracted still further out of the outer housing530, and, as the second bone screw 136 pivots still further within theslotted transverse hole 507, the first bone screw 134 may slidelaterally (i.e., towards the right side of FIG. 27). The elongatedorientation of the second slotted hole 586 along the width W, mayadvantageously add additional freedom to the movement of thenon-invasively adjustable wedge osteotomy device 500 as it distracts thefirst portion 119 from the second portion 121 of the tibia 102, andallow for an increased amount of angulation, for example, a total ofbetween about 10°-22°, about 12°-20°, about 14°-18°, or about 16°, orany other degree of angulation that is clinically meaningful for anygiven patient. Devices (e.g., other non-invasively or invasivelyadjustable wedge osteotomy devices, including those disclosed herein)that do not have both the slotted transverse hole 507 and second slottedhole 586, may be able to achieve about 16° of angulation. However, forsuch devices to do so may cause axial lengthening between the firstportion 119 and the second portion 121 of the tibia 102, as opposed tomerely changing the angle between the first portion 119 and the secondportion 121. Axial lengthening between the first portion 119 and thesecond portion 121 of the tibia may cause unneeded and deleteriousstresses on and/or even fracture of the hinge 450 formed by theconnection between the first portion 119 and the second portion 121 ofthe tibia 102 (shown in FIG. 15). Were the first portion 119 to fracturefrom the second portion 121 and away from the rest of the tibia 102, thefirst portion 119 could be axially or non-angularly distracted away fromthe second portion 121, and would not correct the angle of the kneejoint 104. Therefore, incorporation of both the slotted transverse hole507 and second slotted hole 586 into the non-invasively adjustable wedgeosteotomy device 500 may allow a full 16° of angulation (or more) withlittle to no axial elongation, which can be advantageously achievedwithout significant damage to the hinge 450. In some cases, angulationof up to 25° may be possible while still maintaining the same anteriorto posterior slope on the top surface of the tibia 102.

In some embodiments, an alternative to the slotted transverse hole 407,507 may be used. FIGS. 33-34 illustrate an hourglass shaped hole forenabling pivoting of a bone screw. Wall 602 (for example, ofnon-invasively adjustable wedge osteotomy device 600) may have a taperedor hourglass-shaped hole 606 passing through the wall 602. The taperedor hourglass-shaped hole 606 may have a circular cross-section thatvaries in diameter along its length. As the wedge osteotomy devicedistracts/retracts, as disclosed herein, the second bone screw 136 isallowed to pivot, for example, from the position in FIG. 33 to theposition in FIG. 34. The degree of pivot is directly dependent on thevariance in diameter: the larger the outer diameter, the more pivot isallowed. It is contemplated that embodiments of the tapered orhourglass-shaped hole 606 may peiinit pivot angles (i.e., the degree ofmaximum pivot to maximum pivot, such as the angular difference betweenthe second bone screw 136 shown in FIG. 33 to the second bone screw 136shown in FIG. 34) of between about 5°-40°, about 10°-35°, about 15°-30°,and about 20°-25°, or any other angle that is clinically meaningful forany given patient.

In some embodiments, other alternatives to the second slotted hole 586,as illustrated in FIGS. 35-37, may be used. FIGS. 35-37 illustrate aneccentric bearing type hole for enabling pivoting of a bone screw. Forexample, hole 626 may be incorporated into the wall of a non-invasivelyadjustable wedge osteotomy device as is disclosed herein, such asnon-invasively adjustable wedge osteotomy device 620. In someembodiments, the hole 626 is configured to extend in a generallyanterior to posterior/posterior to anterior orientation when thenon-invasively adjustable wedge osteotomy device 620 is implanted in thetibia 102. In other embodiments, the hole 626 is configured to extend ina generally medial to lateral/lateral to medial orientation when thenon-invasively adjustable wedge osteotomy device 620 is implanted in thetibia 102. In yet other embodiments, the hole 626 extends through thenon-invasively adjustable wedge osteotomy device 620 at an angle betweenmedial to lateral, and anterior to posterior. In some embodiments, thehole 626 may extend through the non-invasively adjustable wedgeosteotomy device 620 at an angle substantially perpendicular to thelongitudinal axis of the non-invasively adjustable wedge osteotomydevice 620. In other embodiments, the hole 626 may extend through thenon-invasively adjustable wedge osteotomy device 620 at an angle notperpendicular to the longitudinal axis of the non-invasively adjustablewedge osteotomy device 620, for example about 1°-30° off perpendicular,about 2°-25° off perpendicular, about 3°-20° off perpendicular, about4°-15° off perpendicular, or about 5°-10° off perpendicular, or anyother angle off perpendicular that is clinically meaningful to any givenpatient. An eccentric bearing 622 may be rotationally held within thehole 626. The eccentric bearing 622 may be made from a lubriciousmaterial (e.g., PEEK, UHMWPE, etc.) so as to advantageously decreasefriction in the system. The eccentric bearing 622 has an off-center hole628 through which an object may be placed (e.g., the first bone screw134). When distracting a non-invasively adjustable wedge osteotomydevice 620 incorporating an eccentric bearing 622 as shown in FIGS.35-37, the off-center hole 628 (and thus any object extending throughthe off-center hole 628, such as the first bone screw 134) rotates inrelation to the hole 626, for example, in a first rotational direction624. FIG. 35 shows a location of approximately seven o'clock; FIG. 36shows a location of approximately ten o'clock; and FIG. 37 shows alocation of approximately two o'clock. The eccentric bearing 622 may befixedly held within the hole 626 of the non-invasively adjustable wedgeosteotomy device 620, for example with snaps, detents, welds, glues,epoxies, or any other means of fixation appropriate for the application.Alternatively, the eccentric bearing 622 may be inserted into the hole626 by a user. The motion of the first bone screw 134 within theeccentric bearing 622 may have characteristics similar to motion of thefirst bone screw 134 within the second slotted hole 586 (discussed withrespect to FIGS. 26-29), though the eccentric bearing 622 may allow someadditional movement of an object extending through the off-center holewith respect to the non-invasively adjustable wedge osteotomy device620, for example vertical (i.e., up and down) movement of an objectextending through the off-center hole 628 in addition to the lateral(i.e., left and right) movement of an object extending through theoff-center hole 628.

In FIG. 38, an elongated hole 702 has been cut or drilled into the upperportion 119 of the tibia 102 in a substantially horizontal fashion. Theelongated hole 702 has a first end 704 (shown here laterally) and asecond end 706 (shown here medially). A non-invasively adjustable wedgeosteotomy device 700, as shown in FIG. 40, may be placed within adrilled or reamed medullary canal within the tibia 102, and a first bonescrew 734 inserted through an anchor hole 716 in the non-invasivelyadjustable wedge osteotomy device 700. In some embodiments, the anchorhole 716 has an internal threaded portion 722 configured to engage amale thread 710 of the first bone screw. The first bone screw 734 has ahead 718 and a distal end 720. The elongated hole 702 (shown in FIGS.38-40) is drilled through the first cortex 712 and the second cortex714. The distal end 720 of the first bone screw may then be insertedthrough the elongated hole 702. In some embodiments, including theembodiment shown in FIG. 40, the male thread 710 engages with the firstcortex 712 thereby cutting partial threads in the bone of the firstcortex 712 and allowing the male thread 710 to pass through the firstcortex 712. Once the male thread 710 has passed through the first cortex712, it is may be threaded into the internal threaded portion 722 of theanchor hole 712, thereby fixing/locking/securing the bone screw 734 tothe to the non-invasively adjustable wedge osteotomy device 700. Becausethe bone screw 734 is only threaded in the middle (i.e., has a smoothneck, and smooth distal end), it may slide or displace along theelongated hole 702 in the upper portion 119 of the tibia 102 from thefirst end 704 to the second end 706, all while the middle threadedportion remains secured to the non-invasively adjustable wedge osteotomydevice 700.

As the non-invasively adjustable wedge osteotomy device 700 isdistracted, the first bone screw 134, 734 is able to follow a path 708(shown in FIG. 38) while the angle of the osteotomy 118 increases and asthe first bone screw 134, 734 moves away from the first end 704 of theelongated hole 702 and towards the second end 706 of the elongated hole702, as shown in FIGS. 38 and 39. In some embodiments, the first bonescrew 134 may be replaced by a pin that inserts through an anchor holein the non-invasively adjustable wedge osteotomy device 700. Such a pinmay be anchored using a close fit, friction fit, snap fit, spring fit,or the like.

FIGS. 41-42 illustrate an embodiment of a non-invasively adjustablewedge osteotomy device 740 which has been implanted and secured to anupper portion 119 of the tibia 102. Among many other elements, that maybe interchangeable with this disclosed elsewhere in this application,the non-invasively adjustable wedge osteotomy device 740 includes acurved anterior-posterior pin 744 and a bone screw 742. Thenon-invasively adjustable wedge osteotomy device 740 may be configured,as described herein with respect to other embodiments, to allow the bonescrew 742 to pivot, displace, slide, or otherwise move duringdistraction or retraction of the non-invasively adjustable wedgeosteotomy device 740. In some embodiments, the curved anterior-posteriorpin 744 has a curved central portion 750 that can be inserted through ahole (such as an anchor hole) of the non-invasively adjustable wedgeosteotomy device 740, a first straight end 746 and a second straight end748.

To insert the curved anterior-posterior pin 744, a hole may be drilledin each of the cortices (anterior to posterior/posterior to anterior) ofthe upper portion 119 of the tibia 102. The curved anterior-posteriorpin 744 may be inserted into the hole in the first side of the firstportion 119, through the non-invasively adjustable wedge osteotomydevice 740, and out of the hole in the second side of the first portion119. Thereby, the curved anterior-posterior pin 744 may rotationallyengage the first portion 119 and the non-invasively adjustable wedgeosteotomy device 740 by using the first straight end 746 and the secondstraight end 748. When the non-invasively adjustable wedge osteotomydevice 740 is distracted, the curved anterior-posterior pin 744 mayadvantageously rotate within the holes (about the first straight end 746and the second straight end 748), thereby allowing the anchor hole ofthe non-invasively adjustable wedge osteotomy device 740 to move in alateral or medial direction and facilitate displacement in multiple axessimultaneously, as described with respect to other embodiments herein.

FIGS. 43-44 illustrate an embodiment of a non-invasively adjustablewedge osteotomy device 900 implanted within a tibia 102. Thenon-invasively adjustable wedge osteotomy device 900 comprises an outerhousing 902 and an inner shaft 904, telescopically located within theouter housing 902. FIGS. 43-44 illustrate two distal bone screws 138,142. But, it should be understood that any number of bone screws may beused. In the same way, FIGS. 43-44 illustrate only a single proximalbone screw 136. Again, it should be understood that this is forillustration purposes only and that more than one bone screw (e.g., 2bone screws) may be used to anchor the non-invasively adjustable wedgeosteotomy device 900 to the first portion 119 of the tibia 102. A secondproximal bone screw (similar to the bone screw 134 of FIGS. 15-20) maybe incorporated and may provide the advantageous benefit of rotationallystabilizing the upper portion 119 and lower portion 121 of the tibia 102in relation to the longitudinal axis of the tibia 102.

In some embodiments, the rotational orientation between the outerhousing 902 and inner shaft 904 is maintained by a longitudinal groove910 on the outer surface of the inner shaft 904 and a radial projection912 extending from the inner surface of the outer housing 902 andconfigured to slide within the longitudinal groove 910. Duringactuation, rotation of screw 136 may pull on the outer housing 902 atlarger angles; consequently, the outer housing 902 and inner shaft 904may advantageously be able to longitudinally translate in relation toeach other. The inner contents of the non-invasively adjustable wedgeosteotomy device may advantageously be protected from the harshenvironment within the body. For example, an o-ring seal 906 may becontained within a circumferential groove 908 in the inner portion ofthe outer housing 902 to provide a dynamic seal between the outerhousing 902 and the inner shaft 904.

In some embodiments, a magnet 914 is rotationally carried by the end ofthe inner shaft 904 via a radial bearing 918. The magnet 914 may becarried within a rotatable magnet housing (not shown). Gear stages 920,922, 924 couple the magnet 914 to a lead screw 926. The lead screw 926is coupled non-rigidly to the output of the final gear stage (i.e., gearstage 924) (e.g., by a coupler 928), and may be held in place by a pin930. The magnet 914 may be rotated by an external moving magnetic field,thereby causing rotation of the lead screw 926. Step-down gear ratiosmay be used so that several rotations of the magnet 914 are necessary tocause one rotation of the lead screw 926. Additional description andexamples of gears stages, such as planetary gear stages, that may beused are included above. In some embodiments, gear stages are notincluded, leaving a 1:1 ratio (i.e., one rotation of the magnet 914causes one rotation of the lead screw 926. The rotation of the leadscrew 926 causes longitudinal movement of a nut 932, which may have adistal fulcrum 934. An inner thread 936 of the nut 932 threadinglyengages an outer thread 938 of the lead screw 926. Rotation of the leadscrew 926 in a first rotational direction 940 causes movement of the nut932 in a first longitudinal direction 942, forcing the distal fulcrum934 against the bone screw 136 at contact location 944, causing the bonescrew 136 and the upper portion 119 of the tibia 102 to generally followa curved path 946, generally around the contact location 944. In someembodiments, some sliding between the bone screw 136 and the distalfulcrum 934 may occur (that is to say that the distal fulcrum 934 is nota pure fulcrum, which is fixed at a single point with no sliding). Thewedge osteotomy 118 is thus caused to open, as shown in FIG. 44. In someembodiments, adjustment of the non-invasively adjustable wedge osteotomydevice 900 does not directly cause longitudinal movement of the outerhousing 902 with respect to the inner shaft 904 (as has been disclosedwith certain other embodiment). Instead, the outer housing 902 and innershaft 904 may passively move longitudinally with respect to each other,to accommodate length change that may occur as a result of the pivotingof the bone screw 136 and the upper portion 119 of the tibia 102 duringthe adjustment (for example from the condition in FIG. 43 to thecondition in FIG. 44).

FIGS. 45-46 illustrate an embodiment of a non-invasively adjustablewedge osteotomy device 950 implanted within a tibia 102. Thenon-invasively adjustable wedge osteotomy device 950 includes an outerhousing 952 and an inner shaft 954, which is telescopically locatedwithin the outer housing 952. FIGS. 45-46 illustrate two distal bonescrews 138, 142. But it should be understood that any number of bonescrews may be used. A first bone screw 134 is used to secure a pivotingmember 956 to the upper portion 119 of the tibia 102. The first bonescrew 134 passes through an anchor hole 958. In some embodiments, theanchor hole 958 is configured to allow rotation between the first bonescrew 134 and the anchor hole 958 of the pivoting member 956. An angledanchor hole 960 through the pivoting member 956 allows the passage of asecond bone screw 136. The angled anchor hole 960 may have a diameteronly just larger than the diameter of the bone screw 136. Therefore,when the bone screw 136 is inserted through the angled anchor hole 960,it is held substantially fixed with respect to the pivoting member 956(i.e., the angled anchor hole 960 does not allow the second bone screw136 to pivot or rock substantially in relation to the pivoting member956). The pivoting member 956 may be coupled to the outer housing 952 bya pivot joint 962. The internal components of the non-invasivelyadjustable wedge osteotomy device 950 may be similar to those describedherein with respect to other embodiments, including those shown in FIGS.5-7.

FIG. 45 shows the non-invasively adjustable wedge osteotomy device 950in a substantially undistracted condition whereas FIG. 46 shows thenon-invasively adjustable wedge osteotomy device 950 in a distractedcondition. As the inner shaft 954 is distracted from the outer housing952, the pivoting member 956, the upper portion 119 of the tibia 102 andthe second bone screw 136 pivot—the second bone screw and the pivotingmember 956 pivot about the pivot joint 962 in relation to the outerhousing 952 and the lower portion 121 of the tibia 102, thus causing thewedge osteotomy 118 to angularly open and the upper portion 119 of thetibia 102 to pivot about the joint/hinge. In some embodiments, thepivoting member 956 may be pivotably coupled to the inner shaft 954,instead of the outer housing 952. In some embodiments, the pivotablejoint 962 may be replaced by a ball joint, which allows additionaldegrees of freedom between the pivoting member 956 and the outer housing952.

Throughout the embodiments presented, a radially-poled permanent magnet(e.g. 368 of FIG. 6) is used as a noninvasively-actuatable drivingelement to generate movement in a non-invasively adjustable wedgeosteotomy device. FIGS. 47-50 schematically show four alternateembodiments, in which other types of energy transfer are used in placeof permanent magnets.

FIG. 47 illustrates an embodiment of a non-invasively adjustable wedgeosteotomy system 1300 including an implant 1306 having a first implantportion 1302 and a second implant portion 1304, the second implantportion 1304 non-invasively displaceable with relation to the firstimplant portion 1302. The first implant portion 1302 is secured to afirst portion of the body 197 and the second implant portion 1304 issecured to a second portion of the body 199 within a patient 191. Amotor 1308 is operable to cause the first implant portion 1302 and thesecond implant portion 1304 to displace relative to one another. In someembodiments, an external adjustment device 1310 has a control panel 1312for input by an operator, a display 1314, and a transmitter 1316. Thetransmitter 1316 sends a control signal 1318 through the skin 195 of thepatient 191 to an implanted receiver 1320. Implanted receiver 1320 maycommunicate with the motor 1308 via a conductor 1322. The motor 1308 maybe powered by an implantable power source (e.g., a battery), or may bepowered or charged by inductive coupling.

FIG. 48 illustrates an embodiment of a non-invasively adjustable wedgeosteotomy system 1400 including an implant 1406 having a first implantportion 1402 and a second implant portion 1404, the second implantportion 1404 non-invasively displaceable with relation to the firstimplant portion 1402. The first implant portion 1402 is secured to afirst portion of the body 197 and the second implant portion 1404 issecured to a second portion of the body 199 within a patient 191. Anultrasonic motor 1408 is operable to cause the first implant portion1402 and the second implant portion 1404 to displace relative to oneanother. In some embodiments, an external adjustment device 1410 has acontrol panel 1412 for input by an operator, a display 1414, and anultrasonic transducer 1416 that is coupled to the skin 195 of thepatient 191. The ultrasonic transducer 1416 produces ultrasonic waves1418 which pass through the skin 195 of the patient 191 and operate theultrasonic motor 1408.

FIG. 49 illustrates an embodiment of a non-invasively adjustable wedgeosteotomy system 1700 comprising an implant 1706 having a first implantportion 1702 and a second implant portion 1704, the second implantportion 1704 non-invasively displaceable with relation to the firstimplant portion 1702. The first implant portion 1702 is secured to afirst portion of the body 197 and the second implant portion 1704 issecured to a second portion of the body 199 within a patient 191. Ashape memory actuator 1708 is operable to cause the first implantportion 1702 and the second implant portion 1704 to displace relative toone another. In some embodiments, an external adjustment device 1710 hasa control panel 1712 for input by an operator, a display, 1714 and atransmitter 1716. The transmitter 1716 sends a control signal 1718through the skin 195 of the patient 191 to an implanted receiver 1720.Implanted receiver 1720 may communicate with the shape memory actuator1708 via a conductor 1722. The shape memory actuator 1708 may be poweredby an implantable power source (e.g., a battery), or may be powered orcharged by inductive coupling.

FIG. 50 illustrates an embodiment of a non-invasively adjustable wedgeosteotomy system 1800 including an implant 1806 having a first implantportion 1802 and a second implant portion 1804, the second implantportion 1804 non-invasively displaceable with relation to the firstimplant portion 1802. The first implant portion 1802 is secured to afirst portion of the body 197 and the second implant portion 1804 issecured to a second portion of the body 199 within a patient 191. Ahydraulic pump 1808 is operable to cause the first implant portion 1802and the second implant portion 1804 to displace relative to one another.In some embodiments, an external adjustment device 1810 has a controlpanel 1812 for input by an operator, a display, 1814 and a transmitter1816. The transmitter 1816 sends a control signal 1818 through the skin195 of the patient 191 to an implanted receiver 1820. Implanted receiver1820 communicates with the hydraulic pump 1808 via a conductor 1822. Thehydraulic pump 1808 may be powered by an implantable power source (e.g.,a battery), or may be powered or charged by inductive coupling. Thehydraulic pump 1808 may alternatively be replaced by a pneumatic pump.

In some embodiments of the wedge osteotomy devices disclosed herein, theslotted holes may be located on the inner shaft instead of or inaddition to the outer housing. The orientation of the implant within thetibia may be opposite of that illustrated in any of the figures.Additionally, any of the embodiments of the non-invasively adjustablewedge osteotomy device may be used for gradual distraction (Ilizarovosteogenesis) or for acute correction of an incorrect angle. And, insome embodiments, alternative, remote adjustment described above may bereplaced by manual control of any implanted part, for example manualpressure by the patient or caregiver on a button placed under the skin.

Of course, the foregoing description is of certain features, aspects andadvantages of the present invention, to which various changes andmodifications can be made without departing from the spirit and scope ofthe present invention. Thus, for example, those of skill in the art willrecognize that the invention can be embodied or carried out in a mannerthat achieves or optimizes one advantage or a group of advantages astaught herein without necessarily achieving other objects or advantagesas may be taught or suggested herein. In addition, while a number ofvariations of the invention have been shown and described in detail,other modifications and methods of use, which are within the scope ofthis invention, will be readily apparent to those of skill in the artbased upon this disclosure. It is contemplated that various combinationsor sub-combinations of the specific features and aspects between andamong the different embodiments may be made and still fall within thescope of the invention. Accordingly, it should be understood thatvarious features and aspects of the disclosed embodiments can becombined with or substituted for one another in order to form varyingmodes of the discussed devices, systems and methods (e.g., by excludingfeatures or steps from certain embodiments, or adding features or stepsfrom one embodiment of a system or method to another embodiment of asystem or method).

We claim:
 1. A system for changing the angle of a bone of a subject,comprising: a non-invasively adjustable implant configured to be placedinside a longitudinal cavity within the bone and comprising: an outerhousing and an inner shaft telescopically disposed in the outer housing,the outer housing associated with a first anchor hole and a secondanchor hole, the first anchor hole configured to pass a first anchor forcoupling the adjustable implant to a first portion of bone and thesecond anchor hole configured to pass a second anchor for coupling theadjustable implant to the first portion of bone, the inner shaftconfigured to couple to a second portion of bone that is separated orseparable from the first portion of bone, such that non-invasiveelongation of the adjustable implant causes the inner shaft to extendfrom the outer housing and to move the first portion of bone and thesecond portion of bone apart angularly; a driving element configured tobe remotely operable to telescopically displace the inner shaft inrelation to the outer housing; and wherein the first anchor hole isslotted with a raised portion located therein and configured to allowthe first anchor to pivot in at least a first angular direction and thesecond anchor hole is configured to allow the second anchor to translatein at least a first translation direction upon the telescopicdisplacement of the inner shaft in relation to the outer housing and amovement of the first portion of bone relative to the second portion. 2.The system of claim 1, wherein the first anchor hole is configured toallow the first anchor to pivot in a second angular direction, oppositethe first angular direction.
 3. The system of claim 1, wherein thesecond anchor hole is configured to allow the second anchor to translatein a second translation direction, opposite the first translationdirection.
 4. The system of claim 1, wherein the inner shaft isassociated with a third anchor hole configured to pass a third anchorfor coupling the adjustable implant to the second portion of bone. 5.The system of claim 1, wherein the first anchor hole is configured toallow the first anchor to pivot in a second angular direction, oppositethe first angular direction, and wherein the second anchor hole isconfigured to allow the second anchor to translate in a secondtranslation direction, opposite the first translation direction.
 6. Thesystem of claim 1, wherein the driving element comprises a permanentmagnet.
 7. The system of claim 6, wherein the permanent magnet comprisesa radially poled rare earth magnet.
 8. The system of claim 1, whereinthe driving element comprises a motor.
 9. The system of claim 1, whereinthe driving element comprises an inductively coupled motor.
 10. Thesystem of claim 1, wherein the driving element comprises anultrasonically actuated motor.
 11. The system of claim 1, wherein thedriving element comprises a subcutaneous hydraulic pump.
 12. The systemof claim 1, wherein the driving element comprises a shape-memory drivenactuator.
 13. The system of claim 1, wherein the driving elementcomprises a piezoelectric element.
 14. The system of claim 1, whereinthe first anchor hole extends substantially along a first planeapproximating a radial section of the adjustable implant and the secondanchor hole extends substantially along a second plane approximating aradial section of the adjustable implant, and wherein the first plane isgenerally orthogonal to the second plane.
 15. The system of claim 14,wherein the first anchor hole and the second anchor hole do not extendperpendicularly to each other.
 16. The system of claim 1, wherein thenon-invasively adjustable implant is configured to change an angle of atibia of a subject having osteoarthritis of the knee.
 17. The system ofclaim 16, wherein the non-invasively adjustable implant is configured tochange the angle of a tibia greater than 12 degrees.
 18. The system ofclaim 16, wherein the non-invasively adjustable implant is configured tochange the angle of a tibia greater than 16 degrees.
 19. The system ofclaim 16, wherein the non-invasively adjustable implant is configured toadjust a mechanical axis in a lateral direction in relation to a kneejoint associated with the tibia.
 20. The system of claim 19, wherein thenon-invasively adjustable implant is configured to adjust a mechanicalaxis to a position that is at least 30% lateral to a central point ofthe knee joint associated with the tibia.
 21. The system of claim 1,wherein the second anchor hole is an elongated slot.
 22. The system ofclaim 1, wherein the second anchor hole has a first diameter and furthercomprising an eccentric bearing having an outer diameter configured toengage the second anchor hole, the eccentric bearing having an innerhole configured to pass the second anchor.
 23. The system of claim 1,wherein the first anchor is a bone screw.
 24. The system of claim 1,wherein the second anchor is a bone screw.